Process of purifying and concentrating glycerine



(No Model.)

0. O. HAGEMANN.

PROCESS OF PUBIFYING AND OONCENTRATING GLYGERINE.

Patented June 9,1891.

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()TTO (lllRlSllAN IIAGEMANN, OF LONDON, ENGLAND, ASSIGNOR TO JAMES S. KIRK & 00,0]? CHICAGO, ILLINOIS.

PROCESS OF PURIFYING AND CO'NCENTRATING GLYCERINE.

SPECIFICATION forming part of Letters Patent No. 453,834, dated June 9, 1891; Application filed September 26, 1890. Serial No. 366,255. (No model.) Patented in England July 1, 1885, No. 7,973

To all whom it may concern.-

Be it known that I, OTTO CHRISTIAN HAGE- MANN, of London, England, have invented certain new and useful Improvementsin Purifyfound that an appreciable quantity of im-" purities passes over together with the mixed vapors of glycerine and water. In order to separate these and obtain liquid glycerine in a pure and concentrated form, 1 cause the vapors to pass through an apparatus such as hereinafter described. The apparatus consists of an upright cylinder or casing'containing shelves or trays, one above the other. The trays are perforated, so that the vapor which enters at the bottom is able to ascend through the apparatus. Condensed liquor accumulates on the trays to a depth which in each case is controlled by an overflow-pipe. This pipe descends to the tray below, and there its lower end dips into a cup or well provided in this tray, and the liquor in the well, rising above the lower end of the pipe, forms a liquid seal and prevents the rise of the vapors through the overflow-pipe. hot ascending vapor at every tray has to force its way through the layer of liquid rest ing on the tray. The lowest tray is the first which the vapor meets and it is the hottest. The liquid upon it is glycerine with little or no water. The vapor in passing throughthis liquid glycerine is washed and deposits inorganic and other impurities. A like action takes place on a tray or trays 'above until practically all the impurities have been washed out. The vapor still ascending through trays which are progressively cooler and cooler, condensation takes place more and more rapidly. At first but littleiwatervapor is condensed, the liquid deposited being a concentrated glycerine; but at each successive tray more water goes down and less glycerine, because a considerable proportion of the latter has already been removed from the vapor and deposited on the trays below. TVhen the apparatus is properly worked, the liquor on the top tray of the se- 'may be allowed to escape.

The.

. point.

ries will be water containing scarcely any glycerine, and the vapor in rising through it will deposit the last of the glycerine, leaving only steam and volatile impurities, which The very weak glyccrine deposited on the upper tray descends by the overflow-pipes from tray to tray, and as it does sothe water, being the more volatile, is evaporated in larger proportion. The water travels upward as vapor, while the 'glycerine travels downward in the liquid state.

On each successive tray in descending the series more and more concentrated glycerine is found, and the product when fully concentrated is drawn off. The outlet is by a pipe passing to the exterior from the well of one of the trays, and several of the-trays may be thus provided with means for drawing off, so that the most suitable level may be selected. If the product be drawn 0% at too high a level, itwill not be sufiiciently concentrated. On the other hand, if it be drawn offat too low a point it will not have been sufficiently-freed from impurities.

-In the drawings, Figure 1 is a vertical section of a suitable apparatus for carrying out my improved process; and Fig. 2 is a sectioual detail of one of the plates D.

A A is a cylinder made in sections, and each section furnished with a jacket A A, through which water may be circulated.

The object of circulating the water through the jacket is to control the temperature of the ascending vapors in the column.

quantity as to maintain the temperature at the top of the column at about boiling-water The water fed in at the top pipe A? fills the jacket of the top section of the 001- 9c umn and becomes heated by the ascending vapors in the column. It then overflows through the siphon A and down into the next section, where it becomes further heated by the ascending vapors, and thence overflows 5 through the siphon A, attached to the middle section of the column to the jacket of the lower section, andfrom thence passes away through the siphon of the lower jacket-section highly heated, usually boiling. The overflow-pipes are made in the form of siphons, so that the uppermost jacket of'the The water 8 l is fed in cold through the pipe A and in such fer to provide aseries of column may be first filled with water, and the water can only descend to the next lower sec-.

holes, preferably conical, and, say, one-tenth of an inch in shortest diameter.

D is a cup or well with which each tray is provided, and a pipe D brings down liquor into the cavity from the tray above. Each tray is furnished with its overfiow-pipe D I prethese columns, such as shown, arranged side by side and connected together in series,the top of one column with the bottom of the. next, The lower part of the first column of the series receives from the still, through the inlet, mixed vapors containing glycerine, water, and suspended impurities.

. The Vapor from bottom of the first column of the series, passes up through the perforations in the trays, and

' at'eaoh stage it bubbles through a shallow j tom of the I glycerine. -I alsodraw oif glycerine from the layer of liquid resting upon the tray. As the vapor progressively cools condensation takes place, glycerine with but little wateris deposited on the lower trays, and on the higher trays mixtures of glycerine and waterin vary" ingproportionshavinglowerand lowerboilingpoints as the exit end of the condenser is'approached. The liquid on the lower and hottest tray stops the'suspended impurities by washin g them out from the ascending vapors. Passing this stage a zone is, arrived at where much glycerine is condensed, while water and impurities more volatile than glycerine pass on. Finally at the end of the series steam (with volatileimpurities) blows out from the condenser, for even at the farther end a temperature of about the boiling-point of water is maintained. T

The numberof columns in use at a time will be varied according to circumstances,

I draw oif purified and concentrated glycerine from one or the other of the wells D of the trays D by taps D also, at the botfirst column I draw off an impure bottoms of the succeeding columns. tile organic impurities will be found more or less in the glycerine from the-last column.

the still, entering at the I usually employ three columns in series, the

first column without jackets.

I. provide two receiversonc for the glycerinc of the purity required and th'e'other for the comparatively impure glycerine. I select the part of the apparatus from which to draw the purified and concentrated glycerine by drawing samples by the taps D I draw the product into the pure-glycerine receiver'by the draw-off cocks nearest to the still, which yields a glycerinecoming up to the standard of purity required. 'When the works ing of the still has been thus adjusted, the operation continues, care only being required to maintain the temperature in the various parts of the condenser without change. The temperatures are observed by the aid of thermometers. These condensing columns are very usefully employed in the concentration of weak solutions of glycerine. In boiling these down in the open or in vacuum much glycerine is at present lost,.which is recovered when the boiling is conducted in a close ve'ssel and the vapor led into a condensing-columnsuch as herein described.

-'The degree of concentration of the productis dependent on the temperature and vapor tension maintained in the condenser. \Vhen the apparatus is of large diameter, I prefer to provide it with a centrally-located pipe or pipes, providing a temperature-co'ntrolling chamber, which may be filled with a heating or cooling'agent.

I claim 1. The herein the purification of glycerine,which consists in passing thedi'stilling-va'pors through successive bodies theproduct of condensation of similar vapors, whereby the water and volatile impurities are driven ofi and .the glycerine is condensed, concentrated, and collected.

2. The herein-described improvement in the purification of glycerine, which consists in passing the distilling-vapors through successive bodies the product of condensation of described improvement in similar vapors confined ina series of closed chambers, whereby the volatile impurities are driven 01f, the suspended impurities collected and removed, and the densed and separated, substantially as described v OTTO CHRISTIAN I IAGEMANN. Witnesses:

OLIVER R. J OHNSQN,

A'. E. MoB RLY,

Consulate Genl. U. S. 11., London.

purified glycerine con; 

